Prorolling of a hydrodrive of brakes is necessary for removal of air which considerably reduces efficiency of braking. Air can get to a hydrodrive owing to system depressurization at repair, replacement of separate knots or a brake liquid.

In air presence in a drive specify the increased course of a pedal of a brake and its "softness". Before air removal check up tightness of all knots of a drive of brakes and their connections.

Carry out prorolling of all system of a drive of brakes in the following sequence:

– The right forward wheel;
– The left forward wheel;
– The right back wheel;
– The left back wheel.

PERFORMANCE ORDER

1. Remove a dustproof cap from the union of prorolling of the wheel cylinder, clear it and put on it the pure transparent hose which other end lower in the capacity partially filled with a brake liquid. The capacity should be at least on 300 mm above the prorolling union. Thanks to it air hit in the cylinder through a carving of the union of prorolling is prevented.

2. Sharply press a pedal of a brake of 3-5 times with an interval 2–3 сек, unscrew on a half-turn the prorolling union at the pressed pedal. Continuing to press a pedal, supersede a liquid being in system together with air through a hose in capacity.

3. After the pedal will reach extreme forward position and вытекание liquids through a hose will stop, will screw the prorolling union home. Repeat these operations, the air outlet from a hose will not stop yet.

4. Keeping a pedal in the pressed position, screw up the prorolling union against the stop and remove a hose.

5. Wipe the union of prorolling and establish a protective cap.

6. Repeat these operations for other wheels.

The prevention

At air removal constantly watch presence of a brake liquid in a tank, without supposing an exposure of its bottom since thus air again will get to system.

7. At absence the pedal should pass in system of brakes of air about half of course. To exclude influence of the vacuum amplifier on prorolling of brakes, air removal make at the idle engine.